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  <meta charset="UTF-8">
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  <title>Document</title>
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<body>
  <script>
    // function Dog(name, age) {
    //   this.name = 'x'
    //   this.age = 1
    // }
    // const d1 = new Dog
    // console.log(d1);
    // console.log(d1.name);
    function fn(){

    }
    // var r = fn
    // var r = fn()
  </script>
</body>

</html>